Foam producing device



Aug. 24, 1937. vy. GOSMANN 2,090,727

FOAM PRODUCING DEVICE Filed Dec. 4, 1935 Fig.1

,,,,,,,,,,,,,,,,,,,,,,mm, 1 i 3 I I a g Q Q g I I mania 0' l L t A. 11/ Illlllllllllll 'IIIIIIIIIIIIIIIIII Patented Aug. 24, 1937 UNITED STATES PATENT OFFlCE FOAM PRODUCING DEVICE Walther Gosmann, Dortmund, Germany, asslgnor to Concordia Elektrizitats-Aktiengesellschaft, Dortmund,, Germany, a joint stock company of Germany 'Application December 4, 1935, Serial No. 52,840 -In Germany December 8, 1934 8 Claims. My invention relatesto improvements in foam producing devices, and more particularly in foam said partition members permitting the passage of the gas and liquid therethrough, and filling the whole cross-sectional area of r the said portion or a substantial part thereof with disconnected filling bodies by means of which the cross-sec- 20 tional area of the portion is divided into numerous small passages of varying cross-sectional area, the liquid and gas under pressure flowing through the said passages continuously changing its-direction and impinging upon the surfaces of the said 25 filling bodies. For varying the consistency of the foam means are provided for varying the passages produced by the filling bodies, and for this purpose means are provided for varying the proportion of the cross-sectional area of the said portion of the 30 tubular member taken by the saidfilling bodies. For the purpose of explaining the invention two examples embodying the same have-been illustrated in the accompanying drawing in which 7 Fig. 1 is a 'diagrammatical elevation showing 35 a fire extinguisher having my improved foam producer connected therewith,

Fig. 2 is a sectional elevation on an-enlarged scale showing the improved foam producer,

Fig. 3 is a similar sectional elevation showing I 40 my improved foam producer with the chamber containing the filling bodies enlarged, and

Fig. 4 is a sectional elevation showing a modification.-

In the following description my improved foam 5 producer will be described as forming a part'of a fire extinguisher. But I wish it to be understood that my invention is not limited to such use.

As is shown in Fig. 1 the fire extinguisher comprises a receptacle 1 forming a supply of liquid 50 and gas under pressure. As is known to those skilled in the art, in a fire extinguisher the said receptacle may be filled with a mineral acid and I a solution of bicarbonate,- which, by coming in contact with each other, generate carbon- 55 dioxide under pressure. Apparatus of this class (cram-94 are known in the art, and my invention is not concerned with the construction and operation of such apparatus, and therefore I deem it not necessary to describe the same in detail.

The receptacle is provided with a tubular member a which preferably is formed with a tapering delivery end a, providing a nozzle. From" the length of the tubular member a chamber g is divided by partition members (3 and c which permit the passage of the liquid and gas therethrough. As shown the partition members take the form of foraminate plates, the holes of the plate 0' which is located at the side of the receptacle I being directed upwardly. ,Within the chamber, g there is a largenumber of solid filling bodies b which fill the whole cross-sectional area of the chamber, as is shown in Fig. 2, or a substantial part thereof, as is shown-in Fig. 3.

The said filling bodies are separate from one another, and preferably they take the form of balls made from a suitable non-corrosive material such as glass or other ceramic material.

Preferably the chamber g is adapted to be changed in length, and for this purpose one of the partitionsand preferably the rear partition 6' is movable longitudinally of the tubular member. .Asshown the partition c is formed with a flange c by means of which it is guided on the inner wall of the tubular member a, the said partition and flange taking the form of a piston. The said piston may be shifted longitudinally of the tubular member a by suitable means. As shown a cam disk d is located within the tubular member a, which disk is fixed to a stem It passed through the wall of the tubular member moutwardly and carrying a wing i by means of which the stem 71. and the cam diskd may be turned. As shown inFigs. 2 and 3, the cam disk is in loose engagement with the partition plate f,

the limit of its movement, and thereby the length I of the chamber g is reduced so far that the filling bodies b fill substantially the whole crosssectional area of the chamber. g, and in the position shown in Fig. 3, the said partition 0' has been pressed rearwardly to the limit of its movement, so that the chamber g has a great length.

Therefore only apart of the cross-sectional 'area of the chamber a is taken by the filling bodies.

The operation of the apparatus is as follows: If it is desired to deliver a foam composed of small bubbles the partition 0 is set by means of the cam. disk d into the position shown in Fig. 2, in which the length of the chamber a is so small that the filling bodies 1) fill substantially the whole cross-sectional area. Therefore the spaces between the filling bodies are small. If new liquid and gas under pressure are delivered through the tubularmember a, the mixture thereof flows through the said small spaces, and it impinges upon the surfaces of the filling bodies and continuously changes the direction of the movement and its cross-sectional area. Thereby liquid and gas are intimately mixedinto a foam composed of small bubbles of gas.

If a foam is desired which is less consistent and which is composed of large air bubbles, the cam disk dis turned. more or less rearwardly thus increasing the length of the chamber 0. Now

' the filling bodies b 'fill only a part of the cross- 25 sectional area of the chamber g. If now liquid and gas under pressure are delivered through the tubular member a, the said liquid and gas fiow through the holes of the partition member. 0', and they are delivered into the chamber gin upward direction. Thereby, and also by the liquid filling the chamber g the filling bodies are thrown upwardly thus filling out the whole chamber 0. However, the spaces or passages between the filling bodies are enlarged as com.- pared to the spaces or passage formed-by the filling bodies in the position of the parts. shown in Fig. 2, and therefore bubbles of larger size are produced.

The filling bodies b may also be made from a suitable elastic and non-corrosive material such as soft rubber. Thereby the size of the bubbles may be further reduced by compressing the said elastic filling bodies and thus further reducing the spaces between the same beyond what is attained in the construction shown in Fig. 2 in which the filling bodies are made from nonelastic material. As a matter of fact, the filling bodies made from rubber may be compressed so far that no passages are left between the same though in' practice, of course, the filling bodies will not be compressed so far.

In Fig. 4 I have shown a modification in which both partitions c and c are fixed to the wall of the tubular member a, and for varying the number of the filling bodies within the chamber g a chamber 1 is provided which is connected with the chamber 9 through a hole 7' made in the wall of the tubular member a, the said hole being adapted to be closed by means of a slide valve k adapted to be shifted by means of a rod m. The chamber 1 is closed by a lid n.. The chamber 1 contains a supply of balls or other filling bodies 17, and the desired number of balls may be transferred from the chamber 1 into the'chamber a.

The operation of the device shown in Fig. 4

1. A foam producing device, comprising a tubular member for the delivery of gas and liquid under pressure provided with spaced partition members dividing therefrom a portion of its length and permitting the passage of gas and liquid, solid filling bodies within said portion of the length of said tubular member filling a substantial part of the cross-sectional area of said portion, means todrive gas and liquid capable ofbeing. formed into a foam through the said portion of the length of the passage and delivering the same through the same partition member, and means to vary in a substantial way the proportion of the' cross-sectional area of said portion taken by said filling bodies.

2. A foam-1 producing device, comprising a tubular member for the delivery of gas and liquid under pressure provided with spaced partition members dividing therefrom a portion of its length and permitting the passage of gas and liquid, solid filling bodies within said portion of the length of said tubular member filling a substantial part of the cross-sectional area of said portion, means-to drive gas. and liquid capable of being formed into foam through said portion of the length of the passage, and ,means to vary in a substantial way the length of said portion.

3. A foam producing de ce, comprising a tubular memberfor the delivery of gas and liquid under pressure, provided with spaced partition members dividing therefrom a. portion of its length and permitting the passage of gas and liquid, said tubular member having a chamber connected with said portion, means for closing said chamber relatively to said portion, and solid filling bodies within said. chamber the number and size of which is sufficient to fill a substantial part of the cross-sectional area of said portion. a

4. A foam producing de ce as claimed in claim 2, in which one of the partition members is shiftable in a substantial degree longitudinally of the tubular member, and a cam disk is provided for shifting the said partition member.

5. A foam producing device as claimed in claim 1, in which the filling bodies take the form of balls.

6. A foam producing device as claimed in claim 1, in which the filling bodies are made from glass.

7. A foam producing device as claimed in claim 1, in which the filling members are made from elastic material and in which means are provided for compressing and deforming said filling members.

8. A foam producing device as claimed in claim 

